Insulator Conductor Semiconductor Intrinsic semiconductor Extrinsic semiconductor N-type semiconductor P-type semiconductor P-N Junction Forward biased Reverse biased Drift Current Diffusion Current Bipolar Junction Transistor (BJT) NPN PNP metal-oxide-semiconductor field-effect transistor

(MOSFET) NMOS PMOS Diode-transistor (DTL) logic Resistor-transistor (RTL) logic Transistor-transistor (TTL) logic Emitter-coupled (ECL) logic Complementary MOS (CMOS) logic Bipolar CMOS (BICMOS) logic